# Connect Cerbo GX MKII to JK BMS

**URL:** <https://community.victronenergy.com/t/connect-cerbo-gx-mkii-to-jk-bms/25096>\
**Category:** DIY\
**Tags:** victron\_community, cerbo\_gx\
**Created:** [13 March 2025 07:36 UTC](https://community.victronenergy.com/t/connect-cerbo-gx-mkii-to-jk-bms/25096 "2025-03-13T07:36:38Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![overhempeter](https://avatars.discourse-cdn.com/v4/letter/o/838e76/32.png) [@overhempeter](https://community.victronenergy.com/u/overhempeter)\
**Post date:** [13 March 2025 07:36 UTC](https://community.victronenergy.com/t/connect-cerbo-gx-mkii-to-jk-bms/25096/1 "2025-03-13T07:36:38Z")

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Hi  
Just got a Cerbo GX MK II and I want to connect my JK BMS to it.  
On the JK BMS there is a RS-485 port.  
So how should I connect it together ?

New at Cerbo so I need some help

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**Author:** ![BipedalPrimate](https://avatars.discourse-cdn.com/v4/letter/b/5f8ce5/32.png) [@BipedalPrimate](https://community.victronenergy.com/u/BipedalPrimate)\
**Post date:** [13 March 2025 09:37 UTC](https://community.victronenergy.com/t/connect-cerbo-gx-mkii-to-jk-bms/25096/2 "2025-03-13T09:37:55Z")

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Review [GitHub - mr-manuel/venus-os\_dbus-serialbattery: Battery Monitor driver for serial battery in VenusOS GX systems](https://github.com/mr-manuel/venus-os_dbus-serialbattery?tab=readme-ov-file)

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**Author:** ![ElKeldo](https://avatars.discourse-cdn.com/v4/letter/e/bbe5ce/32.png) [@ElKeldo](https://community.victronenergy.com/u/ElKeldo)\
**Post date:** [14 March 2025 00:32 UTC](https://community.victronenergy.com/t/connect-cerbo-gx-mkii-to-jk-bms/25096/3 "2025-03-14T00:32:00Z")

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If your JK-BMS has a CAN-bus port, it is probably a better choice to use CAN instead of RS-485.  
On Victron/Cerbo side, the CAN port is already present and should work natively (if you select the right protocol …) , while you will need to add a USB-RS485 module or cable AND add a software module like “dbus serial battery” to get the RS485 connection working.  
On the JKBMS side, the newer and bigger “inverter” models (long rectangular frame) have a CAN-bus port by default, while on the older and smaller models (more square frame) the CAN-bus port is optionnal and must be added by the factory during the construction of the BMS.